O M Edoror and M I Okoruwa

Abstract

The study was carried out to determine the effect of varying levels of cocoa
bean shell with cocoyam peel as replacement for forage grass on growth
indices by grasscutter. Eighteen grasscutter with average weight of 1.00 ±
0.25kg were randomly allotted to three dietary treatments with six animals
per treatment in a complete randomized design. The compared diets were: GG
(70% forage grass and 30% concentrate diet that served as the control diet),
CS30 (30% cocoa beans shell with 40% cocoyam peel and 30% concentrate diet)
and CS40 (40% cocoa bean shell with 30% cocoyam peel and 30% concentrate
diet). The results showed that daily feed intakeand feed conversion ratio
were greater in diet GGthan CS30 and CS40. Treatment diet CS40 was better in
final body weight, total weight gain and daily weight gain. Variation did
not occurin initial body weight of the grasscutter. It can be concluded that
combination of 40% cocoa bean shell with 30% cocoyam peel and 30%
concentrate diet has the potential to enhance growth performance of
grasscutter.

Keywords: agro-industrial by-products, grasscutter, performance

Introduction

Grasscutter has been identified as one of the unconventional livestock that
is capable of solving the problem of low protein intake in the tropics. The
roles presently played by grasscutter in terms of contributing to
nutritional valuesneeded to be sustained, because its production is one of
the ways to ensure sustainable production of bush meat through captive and
ranching wild animals that are tractable and easy to handle (Fatokunet
al2010). However, the survival of grasscutter outside their natural habitat
has created a lot of concern for scientist in the field of wild life farming
all over the world. Thus, there is need to encourage domestication of
grasscutter by making breeding and fattening stock readily available for
intending farmers (Henry 2010). This can be achieved through captive rearing
and finding alternative feed resources for forages that decline in quality
and quantity during the off-season.

The use of cocoa bean shell with cocoyam peel as feed resources could reduce
the pressure on the scarcity of feeds in grasscutter production. Hence the
objective of the study is to determine the growth performance of grasscutter
fed varying levels of cocoa bean shell with cocoyam peel as replacement for
forage grass.

Eighteen young male grasscutter (pups) aged between 2 to 3months old with an
average body weight of 1.00 ± 0.25kg were used for the experiment. The
grasscutter were randomly allocated to the three treatment diets with two
replicates of three grasscutter in a completely randomized design. The
treatment diets were given at the rate of 5% dry matter basis of their body
weight once daily in the morning. Fresh water was provided on daily basis
while routine sanitation with medications was also adhered to strictly. Live
weights measured of the grasscutter were taken on weekly basis and feed
intake was measured daily. The study lasted for 12weeks after 7-day
acclimatization.

Feed stuff was analysed for proximate analysis using the procedure of AOAC
(2002). Data generated from the growth parameters were subjected to analysis
of variance (ANOVA) significant difference between treatments were separated
using Duncan’s multiple range test (SAS 2003)

Results and discussion

The proximate composition of guinea grass, cocoa bean shell and cocoyam peel
are shown in Table 1. The dry matter (DM) content was higher for cocoa bean
shellthan cocoyam peeland guinea grass (Table 1).The values of proximate
composition of guinea grass, cocoa bean shell and cocoyam peel recorded in
this study were comparable to the values reported by Aganga and Tshwenyane
(2004);Babajide and Emiola (2013); Abdulrashid and Agwunobi (2009)
respectively.

Presented in Table 2 is the growth performance of grasscutter fed
experimental diets. Parameters obtained in growth study were varied among
the treatment diets except initial body weight that was not affected. The
effect of the treatment diets on the final body weight was varied between
treatment diets. The values increased progressively in treatment diets as
the levels of cocoa bean shell increased. Grasscutter on CS40 value did not
differ from the value observed for those on CS30 but they had greater values
than those on GG. However, the level of cocoa bean shell inclusion in diets
CS40 and CS30 could probably played an important role in digestion and
absorption (Babajide and Eniola 2013) and positively contributed to enhance
performance of grasscutter on the diets. This could have been possible with
the level of protein availability which had attributed to diets utilization
by the grasscutter. Results showed that total weight gain followed the same
trend as final body weight. Differences observed among treatments on their
effects in total weight gain also suggest the ability of grasscutter to
utilize and convert their test diets to higher total weight gain observed.
However, the higher value recorded in total weight gain for grasscutter
placed in diet CS40 explained the superiority and efficiency of the diet
compared with diets GG and CS30. According to Malik et al (2011) the
nutrient value of a diet and the efficiency of its utilization are largely
determined by the relative balance of glycogenic, energy, long chain fatty
acids and essential amino acid absorbed by the animals. It could then mean
that this diet contained a balance of nutrient which efficiently interacted
to give the highest total weight gain. Notwithstanding, it is interesting to
note that there was a decline in daily weight gain as the level of cocoyam
peel increased gradually in the treatment diets. This depressed growth
observed as the inclusion levels of cocoyam peel increased in the treatment
diets could be attributed to the reduction of their nutrient availability
and utilization. This is supported by the fact that the test diets nutrient
content of cocoyam peel were not better utilize by the grasscutter. During
this course of this study, it was observed that grasscutter on control diet
(GG) spent more time in eating and showed the greater enthusiasm to receive
feed the next morning compared with grasscutter on the test diets (CS30 and
CS40). This partly explains the more feed consumption by the grasscutter on
guinea grass based diet (diet GG) to meet their nutrient requirements. This
results obtained for daily feed intake therefore supported the observation
of Okoruwaet al (2014) that as the level of metabolizable energy in the diet
increases or decreases feed intake changes inversely, although the rate of
adjustment is not always sufficient to keep energy intake constant. This
fact also confirm the report of Ebruaja et al (2017) affirmed that animals
will consume sufficient feed to satisfy their energy requirement which is
one of the main factors limiting feed intake. In addition, the same author
reported that nutrient composition of feeds play an important role in feed
intake of animals. The marked reduction for feed conversion ratio in
grasscutter on diet CS40 further attest the efficiency of the grasscutter to
optimally utilize the feed consumed to maximize daily weight gain.

Moreover, results recorded in this study indicated that CS40 supported
superior final body weight, weight gain and better feed conversion ratio
than CS30 and GG. The reduction in these parameters in control diet and diet
CS30 could be linked with high crude fibre and dustiness respectively. This
could probably be the reason for the decline in performance of grasscutter
on GG and CS30. It has been established that high fibre content of a diet
has the effect of interfering with nutrient utilization and works
synergically with essential fatty acid deficiency in retarding normal growth
in cane rats (Taiwo et al 2009). Okoruwa et al (2004) also observed that
dustiness in a feed induces irritation of the stomach and respiratory organs
in animals.

Conclusion

The resultsobtained from this study showed positive response of using cocoa
bean shell with cocoyam peel as replacement for forage grass in growth
performance of grasscutter.The effect was well pronounced in treatment
containing 40% cocoa bean shell with 30% cocoyam peel and 30% concentrate
diet.

Henry A J 2010
Reproduction performance of grasscutter does at first party reared in a
humid tropical environment. Proceeding of 35th Conference Nigeria
Society for Animal Production.University of Ibadan, Nigeria. Pg
155 – 158